';
buttonsDiv.insertAdjacentHTML('beforeend', HTML);
document.querySelector('#js-btn-clear').onclick = function(e) {
var buttons = document.querySelectorAll('ul.topic_buttons > li > input:checked');
for (var i = buttons.length - 1; i >= 0; i--) {
buttons[i].checked = false;
}
applyFilter([]);
};
}
function generateFlagBtnHTML(langClass) {
var lang = toHumanLang(langClass),
HTML = '';
return HTML;
}
// if user is not logged in, usual selector through div.clear will return null,
// we need to use other selector
function btnDivSelector() {
var btnDiv = document.querySelector('div.clear > ul.topic_buttons');
if (btnDiv !== null) {
return btnDiv;
} else {
return document.querySelector('ul.topic_buttons > li.disabled').parentElement;
}
}
// used as language button OnClick event
function cbOnClick(e) {
var cbChecked = document.querySelectorAll('.topic_buttons li > input[type="checkbox"]:checked'),
enabledLangs = [];
for (var i = cbChecked.length - 1; i >= 0; i--) {
enabledLangs.push(toClassLang(cbChecked[i].id.substr(4)));
}
if (enabledLangs.length > 0) {
applyFilter(getDisabledLangs(enabledLangs));
} else {
applyFilter([]);
}
}
function toHumanLang(lang) {
if ((typeof lang === "string") && (lang.match(/^\.lang_(\w+)/))) {
return lang.substr(6);
} else {
console.error('Bad language string passed to toHumanLang: %s', lang);
return false;
}
}
function toClassLang(lang) {
if (typeof lang === "string") {
var result = '.lang_' + lang;
if (languages.indexOf(result) >= 0) {
return result;
} else {
console.error('Unknown language passed to toClassLang: %s', lang);
return false;
}
}
}
function addStyles(rules) {
var style = document.createElement('style');
style.type = 'text/css';
style.innerHTML = rules;
document.querySelector('head').appendChild(style);
}
// returns array of languages without langs supplied in arguments
function getDisabledLangs(langs) {
var langStr = languages.join(';');
for (var i = langs.length - 1; i >= 0; i--) {
langStr = langStr.replace(RegExp(';?' + langs[i]), '');
}
// if languages[0] is removed, result[0] will be empty, we should remove it;
var result = langStr.split(';');
if (result[0] === "") {
result.shift();
}
return result;
}
// accepts an array of language classes
function applyFilter(langs) {
var rows = document.querySelectorAll('.chapter_row');
for (var i = rows.length - 1; i >= 0; i--) {
rows[i].show();
}
rows = [];
for (var i = langs.length - 1; i >= 0; i--) {
rows = document.querySelectorAll(langs[i]);
for (var j = rows.length - 1; j >= 0; j--) {
rows[j].hide();
}
}
}
})();